Grease composition

ABSTRACT

A grease composition is disclosed comprising (a) a lubricating oil base, (b) a mono or polyurea thickener, (c) a Mannich Base prepared by reacting formaldehyde, phenol and an amine selected from diethanolamine, N,N-diethanol alkylenediamine, and diethylamine, and (d) an alkaline earth metal aliphatic monocarboxylate having from 1 to 3 carbons.

United States Patent Brown et a1.

[451 Feb. 25, 1975 GREASE COMPOSITION Inventors: Stuart Houston Brown,San Rafael;

Richard E. Crocker, Novato, both of Calif.

Chevron Research Company, San Francisco, Calif.

Filed: May 29, 1973 Appl. No.: 364,853

Related U.S. Application Data Continuation-impart of Ser. No. 348,399,April 5, 1973.

Assignee:

U.S. Cl 252/17, 252/51.5 R, 252/5l.5 A, 252/392 Int. Cl. C10m 5/20, ClOm7/32, ClOm 7/30 Field of Search 252/5l.5 R, 51.5 A, 392, 252/17References Cited UNITED STATES PATENTS 12/1943 Fuller 252/5l.5 R

Primary Examiner-Delbert E. Gantz Assistant Examinerl. Vaughn Attorney,Agent, or FirmG. F. Maagdeburger; C. J. Tonkin; M. D. Nelson [57]ABSTRACT A grease composition is disclosed comprising (a) a lubricatingoil base, (b) a mono or polyurea thickener, (c) a Mannich Base preparedby reacting formaldehyde, phenol and an amine selected fromdiethanolamine, N,N-diethanol alkylenediamine, and diethylamine, and (d)an alkaline earth metal aliphatic monocarboxylate having from 1 to 3carbons.

12 Claims, No Drawings closed GREASE COMPOSITION CROSS-REFERENCE TORELATED APPLICATION This application is a continuation-in-part of US.application Ser. No. 348,399 filed Apr. 5, 1973.

BACKGROUND OF THE INVENTION Modern technology is currently supplying thegeneral public and the process industries with machinery capable ofoperating under severe conditions. Many of these machines requirelubricants having properties which are not available with theconventional greases and oils. Thus modernization of the mechanicaldevices has strained the petroleum industry for the development of asecond generation of lubricants capable of satisfying the lubricatingrequirements of the new machines.

Recently, a new grease composition has been developed containing a novelpolyurea thickening agent. This grease has been found to exhibitsuperior endurance and high temperature lubricating properties. Aparticularly advantageous property is that of antithixotropy, i.e., theability to increase in viscosity with increasing shear. The polyureathickening agent is disin US. Pat. Nos. 3,243,210; 3,243,372; 3,346,971;and 3,401,027.

While this grease solves many of the problems associated with the olderlubricants, it is handicapped by a poor rust inhibition. This is atypical problem associated with most multipurpose grease thickeners.Rusting is a major problem in many machines exposed to a corrosiveenvironment. To combat the rust problems, conventional rust inhibitorshave been incorporated into the greases. The conventional inhibitors,however, are quite selective for the particular grease involved andoften interfer with the essential properties of the grease. For example,some inhibitors may impart satisfactory rust inhibition but only at theexpense of adversely softening the grease. Conversely, some inhibitorsmay be quite compatible with the grease but are relatively ineffectivein rust protection.

It is, therefore, an object of this invention to provide an improvedgrease composition.

It is an additional object to provide a polyurea grease compositioncontaining a compatible rust inhibitor.

It is another object of this invention to provide a polymer greasehaving improved rust inhibition.

Other objects and their attendant advantages will become apparent fromthe following description of the invention and appended claims.

SUMMARY OF THE INVENTION The aforementioned objects can be realizied byincorporating into a mono or polyurea containing grease a minor amountof a Mannich Base prepared by reacting phenol with formaldehyde and anamine selected from the class consisting of diethanolamine, N,N-diethanol alkylenediamine, and diethylamine. The molar ratio offormaldehyde to amine to phenol in the Mannich Base product shouldpreferably be between about 0.55:(l.55:l.

By incorporating this particular Mannich Base into the mono or polyureagrease, the rust inhibition of the grease is significantly increased.Concomitantly, the other physical properties ofthe novel grease are notseriously affected.

DETAILED DESCRIPTION OF THE INVENTION The improved grease composition ofthe instant in vention can be realized by admixing in a major portion ofa lubricating oil, from 0.5 to 20 weight percent of a mono or polyureathickener and from 0.] to It) weight percent ofa Mannich Base. TheMannich Base is a mixture of compounds prepared by reacting phenol.formaldehyde and an amine. It is believed that a major portion of thecompounds have the following generalized structure:

(CHIY):

wherein:

x is an integer from 1 to 4 and preferaby from 1 to Y is a univalentamino radical selected from the group consisting of n is an integer from1 to 4 and preferably from 2 to The above structural formula representsa broad and simplified version of the Mannich Base useful in thepractice of this invention. The product is a mixture of compoundswherein x varies from I to 4. In addition. compounds not described bythe above formula may be present, e.g., compounds wherein the hydroxylunit on the phenolic group enters into a reaction with the formaldehydeor amino co-reactant, etc. Other reactions between the three reactantsor any two of them may also take place and the reaction products presentin the mixture. Thus, it is apparent that while the above chemicalformula is descriptive of the majority of the compounds within themixture, it should not be interpreted as limiting the invention to thecompounds having exact structure as shown. The preferred Mannich Base isprepared by reacting phenol, formaldehyde and diethanol amine.

The compounds are prepard by contacting phenol, formaldehyde and aminein a suitable reactor at a temperature of to 400F and preferably from200 to 300F under sufficient pressure to maintain the three reactants inliquid phase, generally from 0 to to 150 psig. The contacting isconducted for a period of 0.5 to 25 hours and preferably from 3 to 20hours. An inert reaction solvent may be employed or the reaction can beconducted with an excess of one or more of the reactants. The solvents,if employed, should preferably be a mutual solvent or posses goodsolvency for the reactants. Exemplary reaction solvents includealiphatic alcohols having from I to 8 carbons such as isobutyl alcohol,pentanol, isopropyl alcohol, etc.

The amount of reactants charged to the reaction vessel usually variesfrom 0.5 to molar parts of formaldehyde and from 0.5 to 5 molar parts ofamine for each molar part of phenol. The preferred molar ratio variesfrom 2 to 4.4 parts of formaldehyde and from 2 to 4 parts of amine perpart of phenol. Mono or Polyurea Thickening Agent The mono or polyureathickening agent as employed in this invention is a water andoil-insoluble organic compound having a molecular weight between about350 and 2,500 AMUs and having at least one ureido group and preferablybetween about 2 and 6 ureido groups. A ureido group as referred toherein defined as The mono or polyurea compound should preferably haveas few terminal primary amine groups, i.e., a compound having a terminal(NH group, as possible and should preferably not have any freecarboxylic acid groups. A particularly preferred polyurea compound hasan average between 3 and 4 ureido groups and has a molecular weightbetween about 600 and 1200 AMUs.

The mono or polyurea compounds are prepared by reacting the followingcomponents:

I A diisocyanate having the formula: OCN-R-NCO wherein R is ahydrocarbylene having from 2 to 30 carbons and preferably an arylenehaving from 6 to carbons and more preferably an arylene having 7carbons;

[I A polyamine having a total of 2 to 40 carbons and having the formula:

R0 R0 R0 H R2 /y H wherein R, and R are the same or different type ofhydrocarbylenes having from I to carbons and preferably from 2 to l0carbons and more preferably from 2 to 4 carbons; R,, is selected fromhydrogen or a C,C alkyl and preferably hydrogen; x is an integer from 0to 2; z is an integer from O to l; and y is an integer equal to 1 when 2is 0 and 0 when 2 is I.

III A monofunctional compound selected from the group consisting ofmonoisocyanate having from 1 to carbons, preferably from 10 to 24carbons, a monoamine having from I to 30 carbons preferably from 10 to24 carbons, or mixtures thereof.

The reaction can be conducted by contacting the three reactants in asuitable reaction vessel at a temperature between about 60 to 320F,preferably from 100 to 300F, for a period from 0.5 to 5 hours andwherein:

n is an integer from 0 to 3;

R is the same or different hydrocarbyl having from I to 30 carbon atoms,preferably from l0 to 24 carbons;

R is the same or different hydrocarbylene having from 2 to 30 carbonatoms, preferably from 6 to l5 carbons; and

R is the same or different hydrocarbylene having from I to 30 carbonatoms, preferably from 2 to 10 carbons.

As referred to herein, hydrocarbyl is a monovalent organic radicalcomposed of hydrogen and carbon and may be aliphatic, aromatic oralicyclic or combinations thereof, e.g., aralkyl, alkyl, aryl,cycloalkyl, alkylcycloalkyl, etc., and may be saturated or olefinicallyunsaturated (one or more double bonded carbons, conjugated ornonconjugated). The hydrocarbylene, as defined in R and R above, is adivalent hydrocarbon radical which may be aliphatic, alicyclic, aromaticor combinations thereof, e.g., alkylaryl. a-ralkyl, alkylcycloalkyl,cycloalkylaryl, etc., having its two free valences on different carbonatoms.

The mono or polyureas having the structure presented in Formula I aboveare prepared by reacting (n+1) mols of diisocyanate with two mols of amonoamine and (n) mols of a diamine. (When n equals zero in the aboveFormula 1, the diamine is deleted.) Mono or polyureas having thestructure presented in Formula 2 above are prepared by reacting (n) molsof a diisocyanate with (n+1) mols of a diamine and two mols of amonoisocyanate. (When n equals zero in the above Formula 2, thediisocyanate is deleted.) Mono or polyureas having the structurepresented in Formula 3 above are prepared by reacting (n) mols of adiisocyanate with (n) mols ofa diamine and one mol ofa monoisocyanateand one mol of a monoamine. (When n equals zero in Formula 3, both thediisocyanate and diamine are deleted.)

In preparing the above mono or polyureas, the desired reactants(diisocyanate, monoisocyanate, diamine and monoamine) are admixed withina suitable reaction vessel in the proper proportions. The reaction mayproceed without the presence of a catalyst and is initiated by merelycontacting the component reactants under conditions conducive for thereaction. Typical reaction temperatures range from 20C to 100C underatmospheric pressure. The reaction itself is exothermic and,accordingly, by initiating the reaction at room temperature, elevatedtemperatures are obtained. However, external heating or cooling may bedesirable.

The mono or polyurea thickener will usually be present in the greasecomposition at a concentration of0.5 to 20 weight percent and preferablyfrom 3 to weight percent and sufficient to thicken the final compositionto the consistency of grease.

Mono or Polyurea Reactants The monoamine or monoisocyanate used in thefor mulation of the mono or polyurea will form the terminala end groups.These terminal end groups will have from 1 to 30 carbon atoms, but arepreferably from 5 to 28 carbon, and more desirably from 6 to 25 carbonatoms.

Illustrative of various monoamines are pentylamine, hexylamine,heptylamine, octylamine, decylamine, dodecylamine, tetradecylamine,hexadecylamine, octadecylamine, eicosylamine, dodecenylamine,hexadecenylamine, octadecenylamine, octadecadienylamine, abietylamine,aniline, toluidine, naphthylamine, cumylamine, bornylamine,fenchylamine, tertiary butyl aniline, hcnzylamine, beta-phenethylamine,etc. Particularly preferred amines are prepared from natural oils orfats or from straight chain acids derived therefrom. These startingmaterials may be converted to amides by reactions with ammonia and theamides dehydrated to give nitriles. The nitriles are then reduced togive the desired amines. Exemplary amines prepared by the method includestearylamine, laurylamine, palmitylamine, oleylamine, petroselinylamine,linoleylamine, linolenylamine, eleostearylamine, etc. The unsaturatedamines are particularly preferred.

Illustrative of monoisocyanates are hexylisocyanates, decylisoeyanate,dodecylisocyanate, tetradecylisocyanate, hexadecylisocyanate,phenylisocyanate, cyclohexylisocyanate, xyleneisocyanate,cumeneisocyanate, abietylisocyanate, cyclooctylisocyanate, etc.

Polyamines, which form internal hydrocarbon bridges between the ureidogroups usually contain from 2 to 40 carbon atoms, preferably from 2 to30 carbon atoms, and more desirably from 2 to 20 carbon atoms. Exemplarypolyamines include diamines such as ethylenediamine, propylenediamine,butylenediamine, hexylenediamine, dodecylenediamine, octylenediamine,hcxadecylcnediamine, cyclohexylenediamine, cyclooctylencdiamine,phenylenediamine, tolylenediamine, xylencdiaminc, dianiline methane,ditoluidinemethane, bis(aniline), bis(toluidine), piperazine, etc.

Triamines such as Namino-ethyl piperazine, diethylenetriamine,dipropylene triamine, tert-N-methyldiethylene triamine, etc., and higherpolyamines such as triethylene tetramine, tetraethylene pentamine,pentaethylene hexamine, etc.

Representative examples of diisocyanates include hexylenediisocyante,decylenediisocyanate, octadecylenediisocyanate, phenylenediisocyanate,tolylenediisocyanate, bis-(diphenylisocyanate), methylenebis(phenylisocyanate), etc.

Another class of mono or polyurea compounds which may be successfullyemployed in the practice of this invention include the following:

5 wherein: n is an integer of 1 to 3, R is defined supra;

X and Y are monovalent radicals selected from Table I below.

In the Table, R is defined supra, R is the same as R and defined supra,R is selected from the group consisting of arylene radicals of 6 to 16carbon atoms and alkenyl groups of 2 to 30 carbon atoms, and R isselected from the grup consisting of .alkyl radicals having from 10 to30 carbon atoms and aryl radicals having from 6 to 16 carbon atoms.

Mono or polyurea compounds described by the above formula (4) can bedescribed as amides and imides of mono, di, and tri ureas. Thesematerials are formed by reacting in the selected proportions suitablecarboxylic acids or internal carboxylic anhydrides, with a diisocyanateand an amine or diamine. The mono or polyurea compounds are prepared byblending the several reactants together in a suitable reaction vesseland heating them to a temperature ranging from F. to 400F. for a periodsufficient to cause formation of the compound, generally from 5 minutesto 1 hour.

Suitable carboxylic acids include aliphatic carboxylic acids of about 1l to 31 carbon atoms and aromatic carboxylic acid of 7 to 17 carbonatoms. Examples of suitable acids include aliphatic acids such aslauric, myristic, palmitic, margaric, stearic, arachidic, behenic,lignoceric acid, etc.; and aromatic acid such as benzoic acid,l-naphthoic acid, Z-naphthoic acid, phenylacetic acid, hydrocinnamicacid, cinnamic acid, mandelic acid, etc. Suitable anhydrides which maybe employed are those derived from dibasic acid which form a cyclicanhydride structure, for example, succinic anhydride, maleic anhydride,phthalic anhydride, etc. Substituted anhydrides, such as alkenylsuecinic anhydride of up to 30 carbon atoms are further examples ofsuitable materials.

Examples of suitable diisocyanates, monoisocyanates, monoamines anddiamines are described supra.

The mono or polyurea compounds are generally mixtures of compoundshaving structures wherein n varies from 0 to 4, or n varies from 1 to3A, existent within the grease composition at the same time. Forexample, when a monoamine, a diisocyanate and a diamine are concurrentlypresent within the reaction zone, as in the preparation of ureas havingthe structure shown in Formula 2, some of the monoamine may react withboth sides of the diisocyanate to form a diurea. In addition to theformulation of diurea. simultaneous reactions can be occurring to formthe tri, tetra, penta, hexa, octa, etc., ureas. Particularly goodresults have been realized when the polyurea compound has an average offour ureido groups.

The lubricating oil generally has a viscosity of 35 to 55,000 SUS at100F and preferably from 20 to 500 SUS at a temperature of 210F.

In a particularly preferred embodiment, an alkaline earth metalaliphatic monocarboxylate is also included within the formulation. Byincorporating the metal carboxylate into the grease composition, thetotal amount of mono or polyurea required to thicken the grease tothedesired consistency can be substantially reduced. 7

Moreover, the presence of the metal carboxylate imparts good extremepressure properties to the grease.

The alkaline earth metal aliphatic monocarboxylate has from 1 to 3carbons. Any of the alkaline earth metals can be employed herein, e.g.,magnesium, calcium, strontium, barium, etc. However, calcium is the mostpreferred. The carboxylate group preferably has from 1 to 2 carbon atomsand more preferably 2 carbon atoms. Exemplary compounds which may besuccessfully employed herein include calcium formate, barium formate,magnesium formate, magnesium acetate, calcium acetate, strontiumacetate, barium acetate, calcium proprionate, barium propionate,magnesium propionate, etc.

The amount of alkaline earth metal aliphatic monocarboxylate presentwithin the grease composition may vary depending upon the lubricatingproperty desired, the particular mono or polyurea constituent selected,the type of alkaline earth metal aliphatic monocarboxylate selected,etc. However, generally the metal carboxylate will range from 3 to 30weight percent of the final grease composition and preferably betweenabout 4 and weight percent. The ratio of alkaline earth metal aliphaticmonocarboxylate to the mono or polyurca constituent will also varydepending upon the afore mentioned conditions, but will generally rangeon a weight basis from 1 to 15 parts of metal carboxylate per part ofmono or polyurea and preferably from 3 to 7 parts per part of mono orpolyurea.

Preparation of Grease Composition The greases exhibiting superiorproperties of this invention are preferably prepared by the in situproduction of the mono or polyurea within the lubricating oil. Ininstances where an alkaline earth metal carboxylate is also employed, itmay also be prepared in situ. In this embodiment, the lubricating oil ischarged to the grease kettle along with the mono or polyurea precursors,i.e.,

the reactants which combine to form the mono or polyurea.

After the formation of the mono or polyurea compounds, the grease kettleis charged with an alkaline earth metal hydroxide or oxide and acarboxylic acid. The ratio of alkaline earth metal hydroxide tocarboxylic acid on an equivalent basis can vary from 1 to 4:1 and ispreferably between 1 and 2:1. The kettle is maintained at a temperaturebetween 70F and 150F during the process to effect the neutralizationreaction of the alkaline earth metal hydroxide or oxide and thecarboxylic acid. During the reaction, water is released and ispreferably removed from the system by applying a slight vacuum on thekettle of to 29 inches of mercury and heating to about 212F and higher.

The Mannich Base made can then be added to the grease composition to theproper concentration. Generally, from 0.1 to 10 weight percent of-theMannie Base will be present in the grease composition for best resultsand more preferably from 0.5 to 2 weight percent.

The grease composition can be further processed by subjecting it toshear hardening. Shear hardening is performed by milling the grease inan extrusion type mill under elevated pressures. This milling improvesthe dispersion of the mono or polyurea and metal carboxylate throughoutthe base oil resulting in a grease of greatly improved consistency. US.application Ser. No. 1 11,517 foled Feb. 1, 1971, now abandoneddiscloses a a preferred method of'shear hardening a grease which can besuccessfully employed for the composition of this invention. OtherAdditives In addition to the thickening agents, alkaline earth metalcarboxylate and Mannich Base rust inhibitor, other additives may besuccessfully employed within the grease composition of this inventionwithout affecting its high stability ad performance over a widetemperature scale. One type of additive is an antioxidant or oxidationinhibitor. This type of additive is employed to prevent varnish andsludge formation on metal parts and to inhibit corrosion of alloyedformation on metal parts and to inhibit corrosion of alloyed bearings.Particularly useful grease antioxidants include phenylalpha-naphthylamine, bis-(alkylphenyl)amine, N,N- diphenyl-p-phenylenediamine,2,2,4-trimethyldihydroquinoline oligomer, bis(4-isopropylaminophenyl)ether, N-acyl-p-aminophenol, N-acylphenothiazines,N-hydrocarbylamides of ethylenediamine tetraacetic acid,alkylphenolformaldehyde-amine poly condensates, etc.

Another additive which may be incorporated into the grease compositionof this invention is an anticorrodant. The anticorrodant is employed toinhibit oxidation so that the formation of acidic bodies is suppressedand to form films over the metal surfaces which decrease the effect ofcorrosive materials on exposed metallic parts. A particularly effectivecorrosion inhibitor is sodium nitrite.

Another type of additive which may be employed herein is a metaldeactivator. This type of additive is employed to prevent or counteractcatalytic effects of metal on oxidation generally by formingcatalytically inactive complexes with soluble or insoluble metal ions.Typical metal deactivators include complex organic nitrogen andsulfur-containing compounds such as certain complex amines and sulfides.An exemplary metal deactivator is mercaptobenzothiazole.

In addition to the above, several other grease additives may be employedin the practice of this invention and include stabilizers, tackinessagents, dropping point improvers, lubricating agents, color correctors,odor control agents, etc.

The following examples are presented to illustrate the practice ofspecific embodiments of this invention and should not be interpreted asimitations upon the scope of the invention.

EXAMPLE 1 This example is presented to illustrate the preparation of apreferred polyurea/alkaline earth metal carboxylate grease. A 48-literstainless steel reaction vessel equipped with a stirrer is charged with7,500 grams of a blend of a paraffinic and naphthenic oil having a arestirred for minutes at 130F and thereafter admixed with 6,000 grams ofobase oil and 548 grams of tolylene diisocyanate. The vessel is agitatedand held at a temperature of 150 for a 30-minute period.

The vessel contents are thereafter milled in an extrusion type mill at apressure of 7,500 psi and then heated to 200F. A small sample of thegrease is analyzed and trace amounts of diisocyanate are detected. Anadditional 40 grams of ethylene diamine are charged to the vessel andmixed with the milled grease for a period of 10 minutes at a temperatureof 210F. At the end of the 10-minute period, the vessel is cooled to150F. At the end of the 10-minute period, the vessel is cooled to 150Fand 5,000 grams of additional base oil with 2,480 grams of hydrated lime(Ca(OH) are charged to the vessel. The lime and base oil are admixedwith the previously milled grease for 5 minutes at which time anadditional 5,460 grams of base oil and 2,800 grams of acetic acid areslowly charged to the vessel over a -minute period. The admixture isagitated for minutes at 150F to assure that the neutralization reactionbetween the calcium hydroxide and acetic acid is complete. Thereafter,an aqueous solution of 320 grams ofa commercial sodium nitrite rustinhibitor is charged to the vessel and the contents milled at 7,500 psi.The grease is heated to 250F to remove water and then cooled to 160F.The grease is then admixed with 8,920 grams of base oil and recycledthrough a mill at a pressure of 7,500 psi. The product grease has anundisturbed penetration (P of 232 and after 60 strokes a workedpenetration (P of 286 (ASTM 217). The ASTM dropping point is about 460F(ASTM-D 2265).

A sample of the grease is calculated to have the following:

wherein T0 is a tall oil radical.

EXAMPLE 2 10 EXAMPLE 3 A 2-liter flask is chargd with 23.5 grams ofphenol, 33 grams of formaldehyde. 162 grams of aminopropyl diethanolamine and ml of isobutyl alcohol. The contents are heated to refluxunder atmospheric pressure and maintained at those conditions for 20hours. The solvent is then stripped from the product. The product isanalyzed and found to contain 13.9 weight percent nitrogen.

EXAMPLE 4 A 2-liter flask is charged with 23.5 grams of phenol, 33 gramsof formaldehyde, 73.1 grams of diethylamine and 125 ml ofisobutylalcohol. The contents are heated to reflux under atmospheric pressureand maintained at these conditions for 20 hours. The solvent is thenstripped from the product. The product had an alkalinity value of 454mgKOI-l/gram.

EXAMPLE 5 This example is presented to illustrate the effectiveness ofthe Mannich Bases of this invention as compared to other comparableMannich Bases. The preparation of the instant Mannich Base issubstantially the same as described in Example 2, the reactant havingbeen present in a ratio of 4.4. mols of formaldehyde and 4 mols ofdiethanol amine for each mol of phenol employed. The Mannich Base isreferred to as C H OH/CH O/NH(C H OH) The comparison Mannich Base isprepared substantially as above except that tetrapropenyl phenol issubstituted for the phenol above. It was made by reacting 4.4 mols offormaldehyde and 4 mols of diethanol amine for each mol of tetrapropenylphenol. This base is referred to as Alk- C H OH/CH O/NH(C H OH).

The Mannich Base prepared by Example 3 is referred to as C H OH/CHO/NH-C H N(C H OH) The Mannich Base prepared by Example 4 is referred toas C H OH/CH O/NH(C H Thereafter, varying amounts of the Mannich Basesare incorporated into a grease prepared substantially by the method ofExample 1 except containing 3.9 wt percent of the polyurea thickener,12.9 wt percent of the calcium acetate, about 2 wt percent NaNO and ablend of paraffmic base oils having a viscosity of 55 SSU at 210F.

The following Table 1 illustrates the effect of the Mannich Bases on thehardness of the grease as measured by ASTM D217 (worked penetration). Onthose greases which were not substantially affected, a modified AASTMD-l743 rust test is performed with 3 percent synthetic sea water (ASTM665) and 97 percent distilled water. The rust test rating; is 0 no rustand 5 very rusty with intermediate values between 0 and 5 representingincreasing degrees of rust. This rating system is more fully describedin IR 220 (British Institute of Petroleum) and is sometimes called theEmcor rating system. Ratings are determined after the bearing is storedfor 1 day at 77F.

TABLE 1 Properties of Mono or Polyurea Grease TABLE l-ContinuedProperties of Mono or Polyurea Grease Worked ASTM Content Pen. Rust Ex.Type of Additive (wt /r) (P Rating 3 same 2.5 313 4 AIk-C H OHICH OINH-(C H,OH) S 439 5. same 25 439 6 C H OH/CH O/NH C;,H,;N-

C,H,0H) 294 0 7 C H OH/CH O/NH(C H l 290 0 8 C.,H OH/CH O/NH,C H OH* l296 3 *Prepared by the steps recited in Ex. 2 except substitutingethanol amine for the diethanol amine.

The above table clearly illustrates the superiority of the Mannich Baseof the present invention over the comparable Mannich Bases. As shown, inExperiments 2 and 3 (employing a Mannich Base of the instant invention),the additive slightly hardened the grease from 319 to 311 or 313 whereasin Experiments 4 and 5, the

additive significantly defeated the thickening action of the polyurea bysoftening the grease to a penetration of 439.

The above table also illustrates the excellent rust inhibition fromusing the claimed Mannich Bases over a close homolog (comparison ofExperiments 2, 3, 6 and 7 with Experiment 8).

EXAMPLE 6 This example is presented to illustrate the breadth of theinstant Mannich Bases and the effectiveness of these various bases inreducing rust while not substantially interfering with the physicalproperties of the grease. The Mannich Bases are prepared insubstantially the same manner as described in Example 2. The molar ratioof the various reactants are varied.

The Mannich Bases are incorporated into a polyurea grease prepared bythe method of Example 1 except containing 3.9 wt percent of the polyureathickener and 13.9 wt percent of the calcium acetate and a blend ofparaffinic base oils having a viscosity of 55 SSU at 210F.

The ASTM worked penetration and the ASTM rust rating of the greases aremeasured and reported in the following Table II.

TABLE II Effect of Mannich Base on Mono or Polyurea Grease Mannich BaseAdditive Molar ratio of phenol to formaldehyde to diethanol amine inreaction product.

We claim: 1. A grease composition comprising a major portion of an oilof lubricating viscosity, (1) from 0.5 to 20 weight percent of a waterand oil-insoluble mono or polyurea thickening agent having at least oneureido group and having a molecular weight between about 350 and 2,500,(2) from 3 to 30 weight percent of an alkaline earth metal aliphaticmonocarboxylate having from 1 to 3 carbons, and (3) from 0.1 to 10weight percent of a Mannich Base prepared by reacting phenol withformaldehyde and an amine selected from the class consisting ofdiethanolamine, N,N-diethanol alkylenediamine and diethylamine, themolar ratio of formaldehyde to amine to phenol being between about 0.5and 5:0.5 and 5:1.

2. The grease composition defined in claim 1 wherein i ..NlNrd anal. l mn a t sfatmti wherein n is an integer from 1 to 4.

3. The grease composition defined in claim 1 wherein said Mannich Baseis prepared by reacting between 2 and 4.4 molar parts of formaldehydewith between 2 and 4 molar parts of said amine for each part of saidphenol.

4. The grease composition defined in claim 3 wherein said amine isdiethanolamine.

5. A grease composition comprising l a major portion of an oil oflubricating viscosity, (2) from 3 to 30 weight percent of an alkalineearth metal aliphatic monocarboxylate having from 1 to 3 carbons, (3)from 0.5 to 20 weight percent of a mono or polyurea thickener preparedby reacting a. a diisocyanate having the formula OCN-R-NCO R0 R0 Eliasteat at wherein R, is selected from the group consisting of hydrogen, aC -C alkyl or mixtures thereof;

R and R are the same or different type of hydrocarbylene having from 1to 20 carbons; x is an integer from 0 to 2; z is an integer from 0 to l;and y is an integer equal to 1 when 2 is 0 and 0 when 2 is c. amonofunctional compound selected from the group consisting of C -Cmonoisocyanate, C -C monoamines or mixtures thereof; and (4) from 0.1 to10 weight percent of a Mannich Base prepared by reacting phenol withformaldehyde and an amine selected from the class consisting ofdiethanolamine, N,N-diethanol alkylenediamine and diethylamine, themolar ratio of formaldehyde to amine to phenol being between about 0.5and 520.5 and 5:1. 6. The grease composition defined in claim 5 whereinsaid diisocyanate is tolylene diisocyanate, said polydiethanol aminewith each molar part of said phenol.

10. The grease composition defined in claim 5 wherein said alkalineearth metal aliphatic monocarboxylate is calcium or barium acetate.

11., The grease composition defined in claim 1 wherein said alkalineearth metal aliphatic monocarboxylate is calcium acetate.

12. The grease composition defined in claim 10 wherein said alkalineearth metal aliphatic monocarboxylate is calcium acetate.

1. A GREASE COMPOSITION COMPRISING A MAJOR PORTION OF AN OIL OFLUBRICATING VISCOSITY, (1) FROM 0.5 TO 20 WEIGHT PERCENT OF A WATER ANDOIL-INSOLUBLE MONO OR POLYUREA THICKENING AGENT HAVING AT LEAST ONEUREIDO GROUP AND HAVING A MOLECULAR WEIGHT BETWEEN ABOUT 350 AND 2,500,(2) FROM 3 TO 30 WEIGHT PERCENT OF AN ALKALINE EARTH METAL ALIPHATICMONOCARBOXYLATE HAVING FROM 1 TO 3 CARBONS, AND (3) FROM 0.1 TO 10WEIGHT PERCENT OF A MANNICH BASE PREPARED BY REACTING PHENOL WITHFORMALDEHYYDE AND AN AMINE SELECTED FROM THE CLASS CONSISTING OFDIETHANOLAMINE, N,N-DIETHANOL ALKYLENEDIAMINE AND DIETHYYLAMINE, THEMOLAR RATIO FO FORMALDIAMINE AND DIETHYBEING BETWEEN ABOUT 0.5 AND 5:0.5AND 5*1.
 2. The grease composition defined in claim 1 wherein saidN,N-diethanol alkylenediamine has the formula:
 3. The grease compositiondefined in claim 1 wherein said Mannich Base is prepared by reactingbetween 2 and 4.4 molar parts of formaldehyde with between 2 and 4 molarparts of said amine for each part of said phenol.
 4. The greasecomposition defined in claim 3 wherein said amine is diethanolamine. 5.A grease composition comprising (1) a major portion of an oil oflubricating viscosity, (2) from 3 to 30 weight percent of an alkalineearth metal aliphatic monocarboxylate having from 1 to 3 carbons, (3)from 0.5 to 20 weight percent of a mono or polyurea thickener preparedby reacting a. a diisocyanate having the formula OCN-R-NCO wherein R isa hydrocarbylene having from 2 to 30 carbons; b. a polyamine having theformula
 6. The grease composition defined in claim 5 wherein saiddiisocyanate is tolylene diisocyanate, said polyamine is ethylenediamine and said monofunctional compound is a C10 to C24 monoamine. 7.The grease composition defined in claim 6 wherein 2 molar parts of saiddiisocyanate are reacted with 1 molar part of said polyamine and 2 molarparts of said monoamine.
 8. The grease composition defined in claim 7wherein said amine is diethanolamine.
 9. The grease composition definedin claim 7 wherein the Mannich Base is prepared by reacting 2 to 4.4molar parts of formaldehyde and 2 to 4 molar parts of diethanol aminewith each molar part of said phenol.
 10. The grease composition definedin claim 5 wherein said alkaline earth metal aliphatic monocarboxylateis calcium or barium acetate. 11., The grease composition defined inclaim 1 wherein said alkaline earth metal aliphatic monocarboxylate iscalcium acetate.
 12. The grease composition defined in claim 10 whereinsaid alkaline earth metal aliphatic monocarboxylate is calcium acetate.